Sheet metal airfield deck mat



G. G. GREULICH SHEET METAL AIRFIELD DECK MAT March 18, 1958 5 Sheets-Sheet 1 Filed Oct. 5, 1955 K m m m Gekub 6 Gweauc/l Mir Mme/s March 18, 1958 Filed Oct. 5, 1953 G- G. GREULICH SHEET METAL AIRFIELD DECK MAT 3 Sheets-Sheet 2 INVENTOR.

BY flaw ri u March 18, 1958 G. G. GREULICH SHEET [METAL AIRFIELD DECK MAT 3 Sheets-Sheet 3 Filed Oct. 5, 1953 INVENTOR.

,GEem-v 6 Pt'UL/Cl/ 154'; Arron/VH5 United States Patent O" SHEET METAL AIRFIELD DECK MAT Gerald G. Greulich, Pittsburgh, Pa.

Application October 5, 1953, Serial No. 384,305

8 Claims. (CI. 94-13) This invention relates to sheet metal mats which are assembled to form airfield decks, and more particularly to the way in which the mats are connected'together and braced to retain their shape and structural strengthunder heavy loads.

It is among the objects of this invention to provide airfield deck mats which are extremely light weight for their strength, which can be moved in either longitudinal direction to connect them side by side, which are connected tightly together at their sides, and which are provided with simple means for quickly and positively connecting adjoining mats end to end.

In accordance with this invention the airfield deck is formed from a plurality of metal mats which are laid with their sides and ends overlapping and detachably connected together. Each mat is formed principally from a plate having corrugations extending lengthwise of it to form laterally spaced troughs. The plate has side flanges projecting outward from the top of the troughs at opposite sides of the mat. The corrugations are prevented from spreading under load by means of parallel tension straps extending across thetop of the plate at relatively short intervals. The straps are secured to the flanges of the plate and between its troughs. One of the flanges is provided at longitudinally spaced intervals with downwardly inclined integral connecting members, each of which has a head extending lengthwise of the plate and connected by .a neck to the flange. The other flange of the plate has its marginal portion turned downward and then outward and is provided with slots extending lengthwise of it for receiving connecting members on an adjoining inclined mat and to permit the heads of those members to be moved lengthwise of the slots beneath the plate between its slots. Preferably, the head of each connecting member extends in opposite directions from its neck, and the outer wall of each slot is provided centrally with an upstanding integral lug for engaging either side of the neck of the connecting member in the slot after an inclined mat has been moved lengthwise to interlock it with the lower mat andthen swingdown to the ground.

To connect the overlapping ends of adjoining mats together, the bottoms of the troughs at the overlapped end have upright integral transverse lugs, at least one of which is provided with a hole through it. The bottoms of the troughs at the opposite end of the mat are provided with transverse slots, most suitably located directly below one of the tension straps, adapted to receive the upright lugs of the overlapped end of a like mat, whereby to connect the two mats together. Pins are disposed in the troughs adjacent their slotted ends and are supported flexible means so that they can be driven through the holes in the lugs that extend up through the slots, thereby locking the lugs in the slots.

; The preferred embodiment of the invention is illustrated in the accompanying drawings, in which: Fig. 1 is a plan view, somewhat diagrammatic, of a portion of an airfield deck formed from my mats;

2,826,970 Patented Mar. 18, 1958 "ice Fig. 2 is an enlarged fragmentary plan view of a single mat; a

Fig. 3 is an enlarged fragmentary plan view of a portion of the deck shown in Fig. 1;

Fig. 4 is a still further enlarged longitudinal vertical section of an end-connecting detail, taken on the line IVIV of Fig. 3;

Fig. 5 is an enlarged vertical transverse section, with its central portion broken away, taken on the line VV of Fig. 3; and

Fig. 6 is a similar vertical transverse section, taken on the line VI-VI of Fig. 3.

All of the sheet metal mats shown connected together in staggered relation in Fig. 1 are made in the same way. All of the mats are the same width, and all but half-length end mats are the same length. One of the mats is illustrated in detail in Fig. 2. It is of general rectangular shape, with connecting members projecting from one side and one end. Each mat is formed mainly from a metal plate 1 provided with corrugations that extend lengthwise of the mat to increase its stiffness and to give it depth. The corrugations form laterally spaced troughs. The corrugations will not flatten under load, even though the plate is relatively thin, because their tops are tied together by a number of tension straps 2. These straps extend transversely across the top of the plate and are secured, such as by spot welding, to the top of the plate between the troughs and to side flanges 3 and 4 that project outward from the tops of the troughs' at opposite sides of the mat. The straps prevent the plate from spreading sideways under heavy strain, without adding materially to the weight of the mat.

The bottom of each trough preferably is flat and its side walls 6 diverge upward, most suitably at an angle of between twenty-five and thirty degrees to the vertical, as shown in Figs. 5 and 6. The tops of the troughs are spaced uniform distances apart by flat horizontal tread areas, which are the parts of the plate that are engaged between straps 2 by the wheels of airplanes on the deck. The tread areas may be provided at suitable intervals with circular holes 7 which serve the triple purposes of reducing the weight of the mats, allowing the soil beneath the mats to dry out, and permitting vegetation to grow up through the mats to camouflage them. The edges of the holes preferably are turned upward to increase the anti-skid properties of the deck, which also are increased by the tension straps. The straps permit the use of wide deep troughs as they form a grid, in combination with the edges of the tread areas or the flat portions of the plate between the troughs, that is comfortable and safe to walk upon and that provides a level nonskid surface for vehicular traffic. The deep, wide troughs thus made possible in the main body of the plate permit the development of great strength with relatively thin or light metal.

In order to connect adjoining mats side by side, one side of each plate is cut to provide it with connecting members 9 integral with the adjoining flange 3. These members are bent downward a short distance, so that they are inclined relative to the top of the mat, generally about fifteen degrees. Each of the connectingmembers has a neck terminating at its outer end in a head Which extends lengthwise of the mat, preferably in opposite directions from the neck. The flange 4 at the opposite side of the plate has its marginal portion turned downward and then outward. This strengthens the flange and also avoids the danger of the edge of'the flange cutting the membrane on which these mats often are laid. The flange 4, including the upper part of its marginal portion, is provided with slots 10 which extend lengthwise of the mat. The slots are directly opposite the connecting members at the other side of the mat and are formed to receive the connecting members on an adjoining mat of like construction.

The side flanges 3 and of theplate are braced stiffened, and strengthened considerably by the ends of the tension straps 2, which are secured rigidly to the flanges between the slots on one side and the necks of connecting members 9 on the other side of the plate. This reinforcing is particularly and increasingly important as thinner metal plates are employed in makingup the mat.

The mat having the connectors that are to be inserted in such slots has to be inclined rather steeply, as indicated in the broken line position in Fig. 6, so that the connectors can be pushed down through the slots in the mat resting on the ground. The raised mat then is moved lengthwise in either direction as far as it will go in order to slide the heads of its connecting members under the adjoining plate between its slots to interconnect the plates. Following this, the raised mat is allowed to swing down to the ground besidethe first one. When this occurs, one side of each connector neck substantially engages one end. of the associated slot as shown in Fig. 3, while the opposite side of the neck is close to one side of a lug 11 that projects upward from the central part of the outer .or lower wall'of the slot. Consequently, as long as both mats are on the ground they cannot be movedlengthwise relative to each other to disconnect them. If, before it was lowered, the raised mat had been moved in the opposite direction, the necks of its connectors 9 would then have swung down into the spaces on the side of lugs 11 Iopposite to the side where the necks appear inthe drawing. Therefore, whichever way a raised mat is moved before it is swung down beside the one that it is being connected to, the lugs in the slots will prevent the mats from becoming disconnected accidentally.

It willbe noted that the slots and connecting members are so related to each other that the connectors engage the substantially horizontal outer walls of the slots arid the lower surface of flange 4 at one end of every slot at the same time. This prevents the connecting members from moving up and down in the slots and practically eliminates vertical slap between the adjoining mats. Also, side play between the mats is avoided by so constructing them that the heads of the connecting members will simultaneously engage and be wedged between the under surface of the downwardly turned flange portion: and the opposing side wall 6 of the adjacent corrugation. This arrangement causes adjoining mats to constantly push away from 'each other, thereby making it unnecessary to stretch the deck sideways, after it is laid, to take up slack.

The mats overlap at their opposite ends and are fastened together there in order to strengthen the deck and make .it more of an integral unit. Accordingly, one end of each corrugated plate is formed for receiving the overlapping end of the adjoining mat. This is done by cutting slots 13 in the ends of the tread areas of the plate so .that the end portions of the troughs between the slots can be spread out to increase their width enough to receive the ends of the troughs of the overlapping mat in nesting relation. Also, to allow the tops of the mats to lie in the same plane, the slotted end of each plate is offset downward the thickness of the metal as shown in Fig.4. The bottom of one or more of these downwardly ofiset troughs is cut inward from its end to form a tongue or lug 14 that is bent upward at right angles. At the opposite end of the mat the bottoms of the same troughs that. have the lugs are provided with transverse slots 15 for fitting over and receiving the lugs on the mat that they overlap. These slots are directly beneath one of the, tension straps 2 so that the underlying lugs will be protected by the strap from the wheels of an airplane on the deck. Also, the strap protects the plane tires from being cut by the lugs.

Although the registering lugs and slots connect the ends of the mats together to some extent, it is desired that means he provided for locking the lugs in the slots.

For this purpose it is preferred that at least one of the lugs on each mat be provided with a hole 16 through it, into which a locking pin 17 can be driven. In the mat illustrated, each lag is provided with such a hole and there is a pin for each hole. It also is desirable that the pins be permanently connected to the mats so that they will be in place and ready for use when the mats are laid. This can be done by locating each pin in one of the troughs and fastening it to the mat by flexible means, which most suitably is a flexible metal strap 18 that has one end welded to the bottom of the tension strap next to the end strap. The outer end of the strap is perforated and receives the pin. The strap is bent up behind the head of the pin to hold the pin in the strap, and the tip of the strap is bent down against the pin to form a stop 19 that limits the distance the pin can be driven through a lug hole. In this way, projection of the pin the desired distance from both sides of the lug is assured.

The flexible straps originally are provided with several deep transverse corrugations so that they will support the pins inward of the adjacent slots 15. After the mat has been laid over the end of an adjoining mat and the lugs 14 of the latter extend up through the slots 15 of the former, each pin is driven ahead through the adjacent lug hole by means of a hammer or the like. This can be done because the corrugated strap 18 will stretch and straighten to someextent to allow the pin to, move ahead. The strap also prevents the pin from working back out of the hole. Yet, if it is desired to disconnect the mats, the pins can readily be driven back out of the lug holes because the flexible straps will bend to permit it.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. An airfield deck comprising a plurality of metal mats laid side by side with like mats to form an airfield deck, each mat comprising a plate having corrugations extending lengthwise thereof and forming laterally spaced troughs, the plate having side flanges projecting outward from the top of the troughs at opposite sides of the mat,

one of the flanges being provided at longitudinally spaced intervals with downwardly inclined integral connecting members each having a head extending lengthwise of the plate and connected by a neck to the flange, the other flange having its marginal portion turned downward and being provided with slots extending lengthwise of it receiving connecting members on an adjoining mat moved lengthwise to position the heads of those members beneath said plate between said slots, and said heads on each plate being at least as wide as the space beneath said flange on the adjoining plate between the marginal portion of that flange and the side wall of the adjacent corrugation, whereby the heads on each plate will engage simultaneously the under surface of the downwardly turned flange portion and the opposing side of the adjacent corrugation of the adjoining mat to prevent side play be tween connected mats.

2. An airfield deck comprising a plurality of metal mats laid side by side with like mats to form an airfield deck, each mat comprising a plate having corrugations extendinglengthwise thereof and forming laterally spaced troughs, the plate having side flanges projecting outward from the top of the troughs at opposite sides of the mat, one of the flanges being provided at longitudinally spaced intervals with downwardly inclined integral connecting members each having a head extending lengthwise of the plate and connected by a neck to the flange, the other flange having its marginal portion turned downward and being provided with slots extending lengthwise of it receiving connecting members on an adjoining mat moved lengthwise to position the heads of those members beneath said slotted flange between said slots, and the slots extending down into said marginal portion of the flange a distance substantially equal to the thickness of the plate so that connecting members in the slots will engage the outer walls of the slots and the bottom of said plate to prevent vertical play between connected mats.

3. A metal mat adapted to be laid with like mats to form an airfield deck, said mat comprising a plate having corrugations extending lengthwise thereof and forming laterally spaced troughs, one end of the troughs being widened to receive one end of an overlapping mat, the bottom of said widened end of a trough having an upright integral transverse lug provided with a hole through it, the bottom of a trough at the opposite end of the mat being provided with a transverse slot adapted to receive an upright lug on the overlapped end of a like mat to connect the two mats together, a locking pin adapted to be inserted in said lug hole, and means secured to the pin and mat for holding the pin before said insertion.

4. A metal mat adapted to be laid with like mats to form an airfield deck, said mat comprising a plate having corrugations extending lengthwise thereof and forming laterally spaced troughs, one end of the troughs being widened to receive one end of an overlapping mat, some or the bottoms of said widened end of the troughs having upright integral transverse lugs, at least one of the lugs being provided with a hole through it, the bottoms of the troughs at the opposite end of the mat being provided with transverse slots adapted to receive the upright lugs on the overlapped end of a like mat to connect the two mats together, a locking pin adapted to be inserted in said lug hole, and flexible means connecting the pin with the rest of the mat so that the pin can be driven into said hole.

5. A mat in accordance with claim 4, in which said flexible means is a corrugated metal strap.

6. A metal mat adapted to be laid with like mats to form an airfield deck, said mat comprising a plate having corrugations extending lengthwise thereof and forming laterally spaced troughs, one end of the troughs being widened to receive one end of an overlapping mat, the plate having side flanges projecting outward from the top of the troughs at opposite sides of the mat, tension straps extending across the top of the plate and secured to it at said flanges and between said troughs, some of the bottoms of said widened end of the troughs having upright integral transverse lugs each provided with a hole through it, the bottoms of the troughs at the opposite end of the mat being provided with transverse slots adapted to receive upright lugs on the overlapped end of a like mat to connect the two mats together, pins disposed in said troughs adjacent their slotted ends, and flexible corrugated metal straps in the troughs having one end supporting the pins and the opposite end supported by one of said tension straps, said corrugated straps being adapted to straighten as the pins are driven through the holes in tugs extending through the slots to lock the lugs therein.

7. A metal mat adapted to be laid with like mats to form an airfield deck, said mat comprising a plate having corrugations extending lengthwise thereof and forming laterally spaced troughs, one end of the mat having slots between the tops of the troughs, the ends of the troughs between the slots being oflset downward and widened to receive one end of an overlapping mat, some of the bottoms of said wide ends of the troughs having upright integral transverse lugs, the bottoms of the troughs at the opposite end of the mat being provided with transverse slots adapted to receive upright lugs on the overlapped end of a like mat to connect the two mats together, and means for locking the lugs in the slots.

8. A metal mat adapted to be laid with like mats to form an airfield deck, said mat comprising a plate having corrugations extending lengthwise thereof and forming laterally spaced troughs, one end of the troughs being widened to receive one end of an overlapping mat, the plate having side flanges projecting outward from the top of the troughs at opposite sides of the mat, tension straps extending across the top of the plate and secured to it at said flanges and between said troughs, some of the bottoms of said widened end of the troughs having upright integral transverse lugs, the bottoms of the troughs at the opposite end of the mat being provided directly below one of said straps with transverse slots adapted to receive upright lugs on the overlapped end of a like mat to connect the two mats together, and means for locking the lugs in the slots.

References Cited in the file of this patent UNITED STATES PATENTS 2,352,892 Greulich July 4, 1944 2,353,398 Greulich July 11, 1944 2,359,548 Cushwa, et a1 Oct. 3, 1944 2,639,650 Robishaw May 26, 1953 

